The present invention relates to a garage door opening remote transmitter antenna and particularly to a passive antenna mounted to a vehicle accessory, such as a visor.
Remote controlled garage door opening mechanisms have become nearly a standard feature for American homeowners. Such garage door opening mechanisms operate utilizing the transmission of a modulated RF frequency signal encoded for security. The signal is transmitted by a remote transmitter, which in the past has been pretuned to a corresponding frequency associated with the garage door opening receiver located in the garage. Such transmitters are typically portable and frequently are picked up and aimed in the direction of the garage door by the vehicle operator in order to control the garage door from an effective distance, allowing ingress of the vehicle as it approaches the garage.
With the revolution of the programmable, multi-channel garage door opening transmitter, which can be mounted in the vehicle visor, console or other permanent location when its in a vehicle and which can memorize the modulation scheme, frequency and any coding of any existent garage door opening transmitter, convenient and permanent mounting locations for such flexible transmitters are now available. When mounted in a vehicle visor or other convenient location in the vehicle, in some instances and in some vehicle designs, dead spots in the radiation pattern of the transmitter result such that the effective range of the transmitter is not what may otherwise be desired. Thus, although providing a convenient and permanent location for the garage door opening transmitter, such permanent mounting may, in some instances, have signals attenuated by, for example, the A-pillar in the vehicle such that blind spots exist in the use of the transmitter for opening a garage door. This problem manifests itself in the user's inability, for example, to open the garage door as the user approaches the end of the driveway so that the door is fully opened by the time the vehicle reaches the garage area. In order to overcome this problem, the predictability of the location of the transmitter in, for example, a visor was noted, and the passive antenna system of the present invention was created to dramatically improve the radiation pattern provided by such garage door opening transmitters.